Coking retort oven with graduated liner wall



June 17, 1958 v J. BECKER 2,839,453

CoxING RETORT ovEN WITH GRADUATED LINER ,WALL

Filed Oct. 20, 1953 -'0a INVENTOR,

Jos.: PH Becmeaf nited States Patent O COKING RETORT OVEN WITH GRADUATES LINER WALL Joseph Becker, Pittsburgh, Pa., assigner to Koppers Company, Inc., acorporation of Delaware Application october zo, 195s, serial No. ssmzz s claims. (ci. 2oz-223) This `invention relates in general to improvements in oven shown and described in my United States Patent It hasbeen conventional practice up to now to design and build the walls of` such ovens with the `liner brick thickness varying from the bottom of the flue wall to the top of the heating ues toprovide for more uniform heat transfer into the coal charge in the vertical direction. A typical design provides 51/2" thick hner brick for the first four courses at the bottom of the fines, thick liner brick for the next ninercourses, and 4 thick liner brick for the balance of the height of the heating iues. This arrangement is designed to compensate for somewhat higher llame temperatures at the bottom of the heating flues than at the top of the ilues. Another typical oven wall design used inthe past provided several courses of 5 liner brick at the base of the heatingues with the balance of the wall being built of 4" liner brick up to the top of the heating ilues. Another design which has been used provided several courses of Sl/z or 6 thick liner brick at the base of the heating flues with the balance of the wall being built of 5" liner brick up to the top of the heating tlues.

Various other designs also have been used. Most constructions have provided a few courses at the base 'of the heating iues with thicker liner brick to resist erosion from the intense flame at the point of initial combustion of the heating gas. `Above this point the liner brick have been of uniform thickness, or have tapered in thickness from the bottom to the top of the flue, depending on the design of the invidivual oven battery. In all cases, however, the designs used up to now have provided uniform liner brick thickness for the entire lengthV of the oven at any given horizontal plane or elevation. That is, with the design first described above, the thickness of the liner brick for the first four courses was 51/2" for the entire length of the oven from pusher side to coke side, `For the next nine coursesrthe liner thickness was 5. for the entire length of the oven, and the balance of the ovenV Wall up to the topA of the heating ues was 4 for the entire length of the oven. However, in no case in the prior art has any provision been made for tapering the thickness of the liner brick, at a given elevation, from pusher side to coke side of the oven.

The present invention concerns the provision of im* provements in the liner wall structure of the coking chamber and heating wall portions of such type of ovens to permit increasing their coking capacity, more particularly in the horizontal typeof coking retort ovens, through faster coking speeds, by reducing the thickness of the oven Walllinersby 'one inch to cneand one half inch at the 2,839,453 Patented June 17,` 1958 ice wider coke side of their tapered oven chambers, relative to the thickness of the liners at the narrower pusher side of the tapered oven chambers, to facilitate faster heat input into the thicker parts of the coal charges of the individual ovens at the wider sides of the oven chambers.

Accordingly, a main feature of the present invention is the provision of a coke oven battery, particularly of the horizontal type, withV liner Walls at the pusher sideend of greater thickness than the liner walls at the coke side end. t

More specifically the invention comprises the provision of `coke ovens of the `aforesaid type in which the liner thickness` between `the coking chambers and their contiguous heating ues in the adjacent heating walls are graduated from the` pusher side to the wider coke side of the chambers, and also lin which the entirepusher side half of a coking chamber is made of one thickness and the entire coke side half is also made of one thickness but of lesser extent. f

Preferably the invention `comprises a graduation in thickness of abouttone inch across the entire heating wall and with the graduation ina series of successive stages of about one-quarter inch difference in thickness as among the successive graduations.

Operating data indicate that approximately F. higher flue temperatures must be carried to maintain the same coking speed with (5") tive inch liners as with (4") inch liners.` At the same iiue temperature, the coking time is approximately (l1/z) one and one-half hours less for a (17) seventeen inch wideoven with (4) four inch liners than for the sameroven with (5) ve inch liners. l l

Accordingly, advantages of reducing `the thickness of theoven liners at thecoke side, where the oven chamber is widest and the cokingA rate must be highest, relative to the narrower pusher side portions of such coking chamber, are that such `reduction in thickness permits faster coking rates at the same maximum iiue temperature than heretofore practiced in this art, and also permits operation with lower maximum flue temperatures in fthat region for the same coking rate, as obtains in the narrower pusher side portions of the same tapered coking charnber.

In coke ovens of this type the coking chambers are high, narrow and elongated chambers contiguous to two heating walls on opposite sides of the respective chambers, which heating walls are, in general, parallel with each other and formed with liner walls on opposite sides ther`eof, which liner walls constitute the `side faces of adjacent coking chambers, when builtside-by-side in a row as conventional for production of metallurgical coke.

AThe heating walls are constituted of brick masonry and the brick liner walls in each heating wall are spaced from each otherA to form combustion flues therein for llame heating alongside coal charges in the oven chambers. With vertically ued combustion dues, the liner walls are interconnected by stretcher walls to form the vertical combustion lues. A t

For discharge of the finished coke in the form of a cake the side faces of the coking chambers are tapered toward the discharge endto facilitate movement of the coke cake as a single unit out through the oven chamber. In practice the thickness of the liner walls has been standardized in the range of 3" to 5, since it has been found that such thicknesses are required for the structural strength required for the normal life expectancy of such commercial ovens.

In the past oven walls have all been built of a uniform` assenso necessary heretofore to maintain a differential heating i operation along each heating wall for uniform heating of the coal charges in the adjoining chambers. Heretofore it has been the practice to maintain a temperature difference of about 100 F. degrees between the two ends of the individual heating walls in order to supply more heat progressively, towards the vcoke side from the pusher' side, in horizontal coke ovens,v and from top to bottom in intermittent vertical ovens, due to the discharge taper of the oven chamber Wall surfaces and their contained coal chamber spaces, to accommodate the pushing, in horizontal ovens, and gravity drop, in intermittent verticals, of the finished coke charges from the coking chambers.

As is pointed out in greater detail in my aforesaid patent, this necessitates a graduation of the air and gas admission to the flues along the heating walls to provide successively greater air and gas admission to the flues, between the end liues, to maintain a temperature difference of about 100 F., in order to attain the same coking time to finish the coking of the charge all-along the chamber, despite the varying thickness and quantity of coal along the length of the oven chamber.

This temperature differential control and regulation is a tedious rand laborious procedure, since the flues usually are heated to a maximum degree just below the temperature at which uxing of the brickwork might occur, and so the differential in temperature of only 100 F., at such high temperature, which is determinable only by `optical measurement from the tops of the flues, requires tedious adjustments to a nicety ofthe gas and air inlets,

or outlets from the ues or their regenerators.

With the graduation in thickness of the liner wall portions by about one inch, for example, from 5" at the pusher side to 4" at the coke side discharge ends of the heating walls, such temperature graduation for such temperature differential is unnecessary and may now be eliminated While still retaining the conventional standards for structuralstrength and long lifeof the ovens.

With this graduation in thickness of the liner walls,

the temperature may be regulated to be held to the same 'i temperature in the ues with completion of coking in the wider parts in thesame coking time as that for the narrower parts of the chambers. In addition it is thereby possible to perform faster coking in the narrower parts than has been possible heretofore, and hence increase the capacity of the chambers to make coke, since it is not necessary with the oven walls of the present invention to hold the heating down below the maximum possible for complete coking of that narrower portion in order to heat the wider thicker portions at a slightly higher temperature for completion of the coking time for those thicker portions at the same time as the completion of the coking 'of the less thick portion of the coking coal charge -in the same chambers,

The novel features of the invention are preferably incorporated in an oven as described in my aforesaid Patent No. 2,100,762 as the preferred form of practicing the present invention with graduation in successive stages of at least four reductions of not more than one quarter inch, since it is impractical in general to manufacture precisely, brick shapes differing in thickness of less than one quarter inch each, and since it is not necessary to provide successively greater reductions in thicknesses for regions opposite successive flues, but only in groups of 4 flues as shown in the accompanying drawings between the end titles.

The regulation of inlets and outlets of the air and gases for combustion in the individual ues, while still required, is however more readilyy performed with ovens built in accordance with the present invention, since the necessity for nicety of adjustment of the regulation for the temperature differential is eliminated.

The end flues, of course, have to be separately adjusted from the adjustment of the heating ues between the end lues, due to the greater radiation of heat from the outer sides of the battery to the surrounding atmosphere.

The features of faster coking with the liner wall structure according to the present invention is best performed, and therefore carried out in its preferred form, in conjunction with the flue bottom regulation of my aforesaid Patent 2,100,762, in order to retain and accentuate the advantages of low pressure differential around the heating flue system that accrues with the greater freedom from counterflow conditions of its cross-over system, with the uniform coking afforded in conjunction with the faster coking of the present invention.

The novel features of the invention, however, lare not limited in all their aspects to conjoint use with the aforesaid features since the novel features are equally applicable to other types of heating ue systems, such as the twin ue, double divided, or other flued systems such as that of Koppers Patent 818,033.

ln addition to the features recited above, the invention has for further objects such other improvements and advantages in construction and operation as may be found to obtain in the structure, arrangements, and operation hereinafter described and claimed.

The accompanying drawings, forming a part of this specification, show for purposes'of Vexempliication, a preferred form and manner in which rtheinvention may be embodied and practiced, but the invention is not to be limited to such illustrative instance or instances.

Figure l is a view showing a Vertical section taken longitudinally through a horizontal coke `oven battery of the Becker type of my aforesaid patent and provided with the present liner wall improvement of their coking chambers and heating walls.

Figure 2 is a horizontal. sectional view showing the graduation in thickness in the same horizontalplanes at the different elevations, such as at the two different elevations as shown on the two section lines II-II of Fig. l, along the heating walls of the liner wall portions between the coking chamber spaces and the combustion ue spaces of the coking chambers and their combustion flues, the left hand half of Fig. 2, showing the stretcher -walls and the right hand half omitting their showing, for greater ease in illustrating the stepped down thickness of the liner wall sections.

The same characters of reference designate the same parts in each of the views of the drawings.

ln the embodiments illustrated in the drawings, the invention is incorporated in a combination coke oven battery, that is, a battery having provision for being tired alternatively with yan extraneously derived relatively lean gas, such as producer gas and blast furnace gas, or with a relatively rich gas such as coke oven gas. For convenience, the present description will be confined to the present illustrated embodiment of the invention in such a combination oven battery; features of the invention may be applied, however, to other structures, for example,` to ordinary so-called coke-ovens tired with coke-oven gas, or ordinary so-.called gas ovens tired with producer gas'or blast furnace gas; hence, the invention is not confined in its scope to the combination oven or to the specic use and specic embodiment in a cross-over flue type oven herein described as an illustrative example.

As the present improvements are useful with various types of coking retort ovens and as the details of such ovens may be readily understood by reference to my-afore-` said patent which is made a descriptive part hereof, a brief description of the various parts of an ovenbattery that are concerned with the present improvements will suce for an understanding of the same.

In general, the coking retort oven comprises a high and narrow coking chamber tapered to increase in width from one end 10a to the other end 10b of two opposite ends of the chamber 10, and provided with a doorway at the latter end 10b. In the case of an intermittent vertical retort oven the discharge end is at the bottom and the oven chamber tapers from the top end toward the bottom end, for` discharge of the coke cake by gravity. In the case of horizontal coke ovens, the coking chambers are tapered, as shown in Fig. 2, from one horizontal end 10a, at which a pusher ram 10c is inserted, to the opposite horizontal end 10b, at which the coke is discharged out of the oven chambers, and are provided as usual with coke oven doors as shown at these opposite ends.

In both types of intermittent ovens, heating walls 11 are provided on two opposite sides of the oven chambers 10 throughout the length and height of the same, and the heating walls 11 are constituted of combustion llues 12 for llame heating the charge in the adjacent chamber.

The heating walls 11 are formed of refractory brickwork and each comprise liner walls 13 on opposite sides thereof disposed between the combustion chamber spaces 12 in the heating walls 11 and the coking chamber space of the chamber 10 in the form of a slot intermediate the heating walls.

The liner walls form the side faces of the coking chambers 10, and conduct the heat from flames of combustion in the combustion chambers 12 directly into coal charges in the oven chambers 10 laterally inwardly of their mass from the two opposite sides thereof.

The heating walls 11 are constructed in general parallelism with each other and heretofore the liner walls 13 Were constituted of the same thickness in any horizontal plane throughout the length of the coking chambers 10, usually of 4" or 5 thick bricks. Conventionally the upper and lower portions of these liner walls are backed up with thicker brickwork 14 than the rest of the liner wall bricks 13 to prevent overheating of the parts of the chambers 10 alongside the region of ignition in the base 15 of the combustion tlues and in the region alongside the crown space 16 where the distillate gas ows along the top charge of coal during coking, and

in such case the brickwork still was of uniform thickness in any horizontal plane of such portions of the heating wall all along the coking chamber.

With the general parallelism of the heating walls 11 as a Whole, relative to each other, and uniformity in thickness of their liner wall portions 13, it has been the custom to build such liner walls 13 to diverge toward the coke side discharge end 10b to facilitate the gravity or pushing discharge of the finished coke cake. This necessitated higher, differential, heating of the wider parts of the coking chambers relatively to the narrower parts thereof to finish the coking of the entire coal mass all along its horizontal length at the same time, thus necessitating regulation and control for dilerential heating in different portions of the heating wall along the horizontal length of the oven chamber 10.

In accordance with the present invention, the liner bricks forming the liner wall portions 13 at the different horizontal planes, are, throughout substantially the full height of the combustion ues, of lesser thickness in portions alongside wider parts 17 of the tapered oven chambers 10 than the thickness of portions alongside a narrower part 18 of the individual chambers 10. Preferably, a reduction in thickness is carried out whereby the thickness` alongside the wider coke side discharge end 10b is about 4 inches and the thickness alongside the narrower, pusher side 10a of the same' chamber is about 5 inches thick.

The advantages and benefits of such graduation in thickness may be attained to a considerable degree with the use of liner walls which are of one thickness all alongside the narrower horizontal half 13a of the adjacent coking chamber, and which are of one lesser thickness all alongside the wider horizontal half 17a of the adjacent coking chambers 10.

Preferably, the thickness of each liner wall 13 is graduated, as sho-wn in Fig. 2, from the narrowest end 10a to the widest end 10b of the tapered coking chambers 10 in a series of wall portions 19 of successively decreasing thickness, progressively, in any single horizontal plane or elevation of the wall 11, in the direction of the wider end 10b of the tapered chambers 10, the dilerence in thickness for each stage 19 being, preferably one quarter inch and so, in a wall as shown, with 24 ues 12, a total one inch reduction carried out in ve sections 19.

The many benefits that accrue from the present invention are attained in a better way with the horizontal coking chamber 10 arranged in a battery with vertical combustion lues 12 as indicated in Figs. 1 and 2, wherein each horizontal slot chamber 10 and its heating walls Il, are in the form of a battery of a series of alternate coking chambers with a heating wall -11 intermediate each two coking chambers 10 arranged side-by-side in a row. As shown the liner walls 13 are interconnected, as conventionally, by stretcher walls 20 which together with the liner walls 13 form the vertical combustion llues 12.

Each llue 12 is provided at its lower end with a pair of regenerator ports 21, 22, and an inlet nozzle 23 for rich gas, and a pair of crosswise regenerators 24, 2i? are connected with each flue through their regenerator ports as conventional for combination oven underfiring.

The best mode of carrying out the novel feature of the present invention to attain its benefits to greatest extent is in conjunction with the improvements of my aforesaid Patent 2,100,762.

Accordingly, the vertical combustion ilues I2 of each heating wall 11, are interconnected by cross-over flues 26 through upper horizontal flow ducts 27. Said vertical combustion ues terminate at their upper parts 28 belowl the top level 29 for leveled coal charges; which level 29 lconventionally is the lower level of the leveler door (not shown) in the pusher side door 10a through which the tops of the coal charges are levelled to leave above the top of the levelled coal charge a Igas olf-flow space 16 along the crown of the oven chambers 10.

In this structure in accordance with the invention of my aforesaid Patent 2,100,762 all regulation is at the bottom of the vertical iiues 12 by means of restrictions for the regenerator ports 21, 22 and the rich gas inlets 23. The areas of the vertical combustion llues 12, horizontal flow direct means 27, and cross-over llues 26 and communications 30 of the vertical flues 12 at their upper parts 28 with their horizontal llow duct means 27, are made sulliciently large that they have no material eect on the gas dow and in this way the gas tlow through the llues occurs with lesser differences in pressure from inlet to outlet, and less draft is required, and the liner walls 13 are vertically disposed as at 31 throughout the major portion of their height for uniform coking vertically throughout coal charges in the coking chambers 10.

In operation, coal is charged into the oven chambers 10 through their top chargin-g holes 33 in the oven roof 34 and leveled at the top level 29, and heat applied by eombustion of gas and air in the vertical ilues 12, to maintain substantially the same temperatures all along the heating Walls 11, except at the end llues where the temperature is higher because of radiation at the opposite side faces of the battery. All regulation is below the bottoms 15 of the tlues and due to the lesser thickness of the liner walls, 13.

alongside the wider parts 17 of the tapered chambers 10, the mass of coal is fully coked in the same coking time by heat applied laterally inwardly .from the sides of the chamber. The faster coking time with the novel `liner structure takes place up to the level of the communications 30 where the graduation in thickness of the liner walls 13 terminates at the upper part 28 of the walls 11, to restrict the novel heating of the charges by the graduation of the liner walls to a level below such communications 30.

The invention, as described hereinabove, is embodied in particular form and manner but may be variously ernbodied within the scope of the claims hereinafter made.

I claim 1. A horizontal coking retort oven battery comprising, in combination: a series of alternate horizontal coking chambers and intermediate heating walls therefor arranged side-by-side in a row, each of said horizontal cokng chambers being tapered to widen from one horizontal pusher side toward the other coke side of the battery to facilitate horizontal pushing of coked charges out of the chambers through their wider ends, and' each of said heating walls comprising vertical combustion tlues with inlet means for gas and air thereto for upow combustion therein, and liner Wall portions on opposite sides of the heating walls, between the flue spaces therein and the coking chamber spaces on the opposite sides of the respective walls, which liner wall portions are of a thickness at the pusher side of the oven within the range of 31/2 to 5 inches and form the side faces of the adjacent coking chambers and conduct the coking heat directly from the combustion dues in the heating walls to coal charges in the adjacent chambers, liner wall portions that are disposed at different elevations upwardly along the respective heating walls in regions further along toward the wider coke side of the oven chambers being of one to one and one half inches less thickness relative to the thickness of liner wall p01'- tions in corresponding horizontal planes of the same heating wall in regions nearer the narrower pusher side of the chambers, to provide for increasing the capacity of the `coking chambers faster heat input into the wider parts than thereof into the narrower parts of the tapered horizontal coke oven chambers.

2. A regenerative coke oven as claimed in claim 1 and in which the liner thickness is graduated all along the heat ing walls from the pusher side to the coke side in a series of wall portions of successively decreasing thickness progressively in the direction of the coke side of the battery.

3. A regenerative oven as claimed in claim 1 and in which the liner po-rtions alongside the pusher side half of each heating wall are of one thickness and those alongside the coke side half -of each heating wall are of one lesser thickness.

4. A coke oven as claimed in claim 3 and in which the liner wall portions of each heating wall are graduated one inch in decreasing thickness, progressively, in direction from the narrower ends of the adjacent coking chamber towards the wider ends thereof.

5. A horizontal Cokin-g retort oven battery comprising horizontal cokin-g chambers alternating in position side by side with intermediate heating walls therefore, each of said coking chambers being tapered to increase in width from one horizontal pusher side end to the other coke side end and being provided with a doorway at said wider coke side end for discharge of coke horizontally out of the coking chambers attheir wider ends, and having a top level for leveled coal charges, leaving a gas oltake tree space horizontally above said top level, along the crown of the coking chambers, for ott-flow of distillate gas horizontally along the crown over the top of a leveled underlying charge, land each of said heating walls being provided with cross-over ue interconnected vertical combustion lines for upow combustion therein that terminate at their upper parts below said top level for leveled coal charges; and in which each heating wall comprises at dilerent elevations between the tops of the vertical combustion lines and the oven sole, liner wall portions which decrease in thickness between the combustion ue spaces and the col;- ing chambers from the pusher side end ot the oven to the wider coke side end of each of the adjacent coking charnbers for a distance of one to one and one half inch lesser thickness, to provide for increasing coking capacity in the chambers by faster heat input into the coal mass in the wider coke side parts of the chambers than into the narrower pusher side parts of the coking chambers.

References Cited in the le of this patent UNITED STATES PATENTS Re. 15,992 Wilputte Feb. 3, 1925 1,176,066 Koppers Mar. 21, 1916 1,295,796 Roberts Feb. 25, 1919 1,304,597 Plantinga May 27, 1919 1,596,048 Kernohan Aug. 17, 1926l 1,601,741 Roberts Oct. 5, 1926 1,904,191 Becker Apr. 18, 1933 2,100,762 Becker Nov. 30, 1937 2,102,609 Becker Dec.A 21, 1937 2,132,522 Van Ackeren Oct. 11, 1938 2,420,373 Hogberg May 13, 1947 FOREIGN PATENTS 687,624 Germany Feb. 2, 1940 

1. A HORIZONTAL COKING RETORT OVEN BATTERY COMPRISING, IN COMBINATION: A SERIES OF ALTERNATE HORIZONTAL COKING CHAMBERS AND INTERMEDIATE HEATING WALLS THEREFOR ARRANGED SIDE-BY-SIDE IN A ROW, EACH OF SAID HORIZONTAL COKING CHAMBERS BEING TAPERED TO WIDEN FROM THE ONE HORIZONTAL PUSHER SIDE TOWARD THE OTHER COKE SIDE OF THE BATTERY TO FACILITATE HORIZONTAL PUSHING OF COKED CHARGES OUT OF THE CHAMBERS THROUGH THEIR WIDER ENDS, AND EACH OF SAID HEATING WALLS COMPRISING VERTICAL COMBUSTION FLUES WITH INLET MEANS FOR GAS AND AIR THERETO FOR UPFLOW COMBUSTION THEREIN, AND LINER WALL PORTIONS ON OPPOSITE SIDES OF THE HEATING WALLS, BETWEEN THE FLUE SPACES THEREIN AND THE COKING CHAMBER SPACES ON THE OPPOSITE SIDES OF THE RESPECTIVE WALLS, WHICH LINER WALL PORTIONS ARE OF A THICKNESS AT THE PUSHER SIDE OF THE OVEN WITHIN THE RANGE OF 3 1/2 TO 5 INCHES AND FORM THE SIDE FACES OF THE ADJACENT COKING CHAMBERS AND CONDUCT THE COKING HEAT DIRECTLY FROM THE COMBUSTION FLUES IN THE HEATING WALLS TO COAL CHARGES IN THE ADJACENT CHAMBERS, LINER WALLS PORTIONS THAT ARE DISPOSED AT DIFFERENT ELEVATIONS UPWARDLY ALONG THE RESPECTIVE HEATING WALLS IN REGIONS FURTHER ALONG TOWARD THE WIDER COKE SIDE OF THE OVEN CHAMBERS BEING OF ONE TO ONE AND ONE HALF INCHES LESS THICKNESS RELATIVE TO THE THICKNESS OF LINER WALL PORTIONS IN CORRESPONDING HORIZONTAL PLANES OF THE SAME HEATING WALL IN REGIONS NEARER THE NARROWER PUSHER SIDE OF THE CHAMBERS, TO PROVIDE FOR INCREASING THE CAPACITY OF THE COKING CHAMBERS FASTER HEAT INPUT INTO THE WIDER PARTS THAN THEREOF INTO THE NARROWER PARTS OF THE TAPERED HORIZONTAL COKE OVEN CHAMBERS. 